From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751977Ab3LKOxq (ORCPT ); Wed, 11 Dec 2013 09:53:46 -0500 Received: from 7of9.schinagl.nl ([88.159.158.68]:35534 "EHLO 7of9.schinagl.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751385Ab3LKOxp (ORCPT ); Wed, 11 Dec 2013 09:53:45 -0500 Message-ID: <52A87C07.1020102@schinagl.nl> Date: Wed, 11 Dec 2013 15:51:51 +0100 From: Olliver Schinagl User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130803 Thunderbird/17.0.8 MIME-Version: 1.0 To: Tejun Heo CC: Olliver Schinagl , grant.likely@linaro.org, "rob.herring@calxeda.com" , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, dev@linux-sunxi.org, maxime.ripard@free-electrons.com, ijc@hellion.org.uk, hdegoede@redhat.com, Richard Zhu , Shawn Guo , Thomas Petazzoni Subject: Re: [PATCH 2/3] ARM: sunxi: Add an ahci-platform compatible AHCI driver for the Allwinner SUNXi series of SoCs References: <1386159055-10264-1-git-send-email-oliver@schinagl.nl> <1386159055-10264-3-git-send-email-oliver@schinagl.nl> <20131204123708.GD3158@htj.dyndns.org> <529F2677.3070208@schinagl.nl> <20131204131402.GG3158@htj.dyndns.org> <529F2B41.8090009@schinagl.nl> <20131204132312.GH3158@htj.dyndns.org> In-Reply-To: <20131204132312.GH3158@htj.dyndns.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hey all, On 04-12-13 14:23, Tejun Heo wrote: > Hello, > > (cc'ing Richard and Shawn, hi!) > > On Wed, Dec 04, 2013 at 02:16:49PM +0100, Olliver Schinagl wrote: >> On 04-12-13 14:14, Tejun Heo wrote: >>> Hello, >>> >>> On Wed, Dec 04, 2013 at 01:56:23PM +0100, Oliver Schinagl wrote: >>>> I took the imx driver as example, as I wasn't sure on where to >>>> start. But I don't think it's possible yet without improving >>>> ahci_platform as I suggested in the cover letter. So if >>>> ahci_platform needs to be improved, I guess a separate patch series >>>> would be more appropriate? >>>> >>>> So would it be acceptable to have this as the 2nd (and last?) >>>> ahci_platform driver and go from there? Or do you want to block new >>>> ahci_XXX drivers until ahci_platform has been improved? >>> I don't want to block new drivers unconditionally but at least I want >>> to know which direction we're headed in the longer term. Right now it >>> feels like we could be at the beginning of an uncoordinated explosion >>> of these drivers which will take a hell lot mpore effort to clean up >>> after the fact. I could be wrong and these could actually be >>> different enough to justify separate drivers and there isn't gonna be >>> an avalanche of these but again I at least want to know the general >>> direction things are headed before making any decisions. >> I'd be happy to pour it in any form that's needed. I even do the >> modification/rewrite of ahci_platform if I get enough help as it >> might be a little over my head initially ;) >> >> That said, I don't think it's much different at all and I do think >> it could be much simpler. In my mind, the sunxi_ahci driver wouldn't >> need to be much bigger then a few lines that are specific to the SoC >> (hardware init) and registerd to the ahci_platform framework via >> platform_ahci_register() instead of platform_device_register(). >> >> But again, point me (for dummies ;) in the right direction and I'll >> work on it with some help. > Richard and Shawn recently worked on ahci_imx. Can you guys please > talk with each other and figure out what can be done to share as much > as possible among these new platform-specific drivers? I'd really > like to see the common things factored out as much as possible with > only the actual hardware differences described for each device. Working on this and studying the existing ahci_platform/shci_platform drivers the last few days and was figuring out why ahci_platform only supports 1 clock. IMX handles this by having 3 clocks defined in the DT, the first one gets enabled by default via ahci_platform, the other 2 get enabled in IMX's probe function. Is it an idea to extend this to support all clocks that would be required (via a callback)? Or do we prefer having the clocks separated for other technical reasons? Or do we want to handle the clocks via the ahci_platform framework and extend hpriv->clk to an array of clocks? Oliver > > Thanks a lot! >